Upgrade your home theater system and enjoy exceptional surround sound with the MSurround Loudspeaker from Boston Acoustics. Along with a 3.5-inch polypropylene cone woofer, the MSurround features a 2.5-inch Balanced Mode Radiator (BMR) driver for consistent sound across a wide audio range. The speaker is short enough to fit easily on shelves and walls and has ports on top to limit proximity effect and optimize performance over a wide range of placement options.